<template>
  <div>
    <!-- 评论列表 -->
    <van-list
      v-model="loading"
      :finished="finished"
      finished-text="没有更多了"
      @load="onLoad"
      class="cmt-list"
      :class="{
        'art-cmt-container-1': isShowCmtInput,
        'art-cmt-container-2': !isShowCmtInput,
      }"
      :immediate-check="false"
    >
      <!-- 评论的 Item 项 -->
      <div class="cmt-item" v-for="obj in commentsList" :key="obj.com_id">
        <!-- 头部区域 -->
        <div class="cmt-header">
          <!-- 头部左侧 -->
          <div class="cmt-header-left">
            <van-image class="avatar" :src="obj.aut_photo" />
            <span class="uname">{{ obj.aut_name }}</span>
          </div>
          <!-- 头部右侧 -->
          <div class="cmt-header-right">
            <van-icon
              name="like"
              size="16"
              color="red"
              v-if="obj.is_liking"
              @click="onLikeFn(obj.com_id, false)"
            />
            <van-icon
              name="like-o"
              size="16"
              color="gray"
              v-else
              @click="onLikeFn(obj.com_id, true)"
            />
          </div>
        </div>
        <!-- 主体区域 -->
        <div class="cmt-body" v-html="obj.content"></div>
        <!-- 尾部区域 -->
        <div class="cmt-footer">{{ formatTime(obj.pubdate) }}</div>
      </div>
    </van-list>
    <!-- 底部添加评论 -->
    <div class="cmt-add">
      <!-- 底部添加评论区域 - 1 -->
      <div class="add-cmt-box van-hairline--top" v-if="isShowCmtInput">
        <van-icon name="arrow-left" size="0.48rem" @click="$router.back()" />
        <div class="ipt-cmt-div" @click="isShowCmtInput = false">发表评论</div>
        <div class="icon-box">
          <van-badge :content="totalCount" :max="99">
            <van-icon
              name="comment-o"
              size="0.53333334rem"
              @click="commentClickFn"
            />
          </van-badge>
          <van-icon name="star-o" size="0.53333334rem" />
          <van-icon name="share-o" size="0.53333334rem" />
        </div>
      </div>

      <!-- 底部添加评论区域 - 2 -->
      <div class="cmt-box van-hairline--top" v-else>
        <textarea
          v-focus
          placeholder="友善评论、理性发言、阳光心灵"
          @blur="blurFn"
          v-model.trim="comText"
        ></textarea>
        <van-button type="default" :disabled="!comText.length" @click="sendFn"
          >发布</van-button
        >
      </div>
    </div>
  </div>
</template>

<script>
import { timeAgo } from '@/utils/date'
import {
  getCommentsAPI,
  commentsLikingAPI,
  deleteCommentsLikingAPI,
  addCommentAPI
} from '@/api'
export default {
  methods: {
    formatTime: timeAgo,
    // 点赞方法
    onLikeFn (id, com) {
      this.$emit('likeFn', id, com)
    },
    // 获取文章评论列表
    async getComments () {
      const { data: res } = await getCommentsAPI(this.commentsObj)
      this.commentsList = [...this.commentsList, ...res.data.results]
      this.totalCount = res.data.total_count || '' // 如果无评论数(0), 给空字符串(防止0微标出现)
      this.commentsObj.offset = res.data.last_id

      if (this.commentsObj.offset === null) this.finished = true
      this.loading = false
    },
    // 点赞评论
    async likeFn (id, com) {
      if (com) await commentsLikingAPI(id)
      else {
        await deleteCommentsLikingAPI(id)
      }
      this.getComments()
    },
    // 点击评论按钮 -> 把第一条评论滑动到最上面
    commentClickFn () {
      document.querySelector('.like-box').scrollIntoView({
        behavior: 'smooth'
      })
    },
    // 发布评论按钮
    async sendFn () {
      const { data: res } = await addCommentAPI({
        target: this.$route.params.art_id,
        content: this.comText
      })
      this.commentsList.unshift(res.data.new_obj)
      this.totalCount++
      this.comText = ''
      this.commentClickFn()
    },
    // 输入框失去焦点
    blurFn () {
      setTimeout(() => {
        this.isShowCmtInput = true
      }, 0)
    },
    // 底部加载更多
    onLoad () {
      if (this.commentsList.length === 0) {
        return (this.loading = false)
      }
      this.getComments()
    }
  },
  data () {
    return {
      loading: false,
      finished: false,
      commentsObj: {
        type: 'a',
        source: this.$route.params.art_id,
        offset: ''
      }, // 评论对象
      commentsList: [], // 评论列表
      totalCount: '', // 评论总数
      isShowCmtInput: true, // 控制添加评论盒子：true显示1， false显示2
      comText: '' // 评论内容
    }
  },
  created () {
    this.getComments()
  }
}
</script>

<style scoped lang="less">
.cmt-list {
  padding: 10px;
  .cmt-item {
    padding: 15px 0;
    + .cmt-item {
      border-top: 1px solid #f8f8f8;
    }
    .cmt-header {
      display: flex;
      align-items: center;
      justify-content: space-between;
      .cmt-header-left {
        display: flex;
        align-items: center;
        .avatar {
          width: 40px;
          height: 40px;
          background-color: #f8f8f8;
          border-radius: 50%;
          margin-right: 15px;
        }
        .uname {
          font-size: 12px;
        }
      }
    }
    .cmt-body {
      font-size: 14px;
      line-height: 28px;
      text-indent: 2em;
      margin-top: 6px;
      word-break: break-all;
    }
    .cmt-footer {
      font-size: 12px;
      color: gray;
      margin-top: 10px;
    }
  }
}
/*美化 - 文章详情 - 底部的评论页面 */
// 外层容器
.art-cmt-container-1 {
  padding-bottom: 46px;
}
.art-cmt-container-2 {
  padding-bottom: 80px;
}
.cmt-add {
  // 发布评论的盒子 - 1
  .add-cmt-box {
    position: fixed;
    bottom: 0;
    left: 0;
    width: 100%;
    box-sizing: border-box;
    background-color: white;
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 46px;
    line-height: 46px;
    padding-left: 10px;
    .ipt-cmt-div {
      flex: 1;
      border: 1px solid #efefef;
      border-radius: 15px;
      height: 30px;
      font-size: 12px;
      line-height: 30px;
      padding-left: 15px;
      margin-left: 10px;
      background-color: #f8f8f8;
    }
    .icon-box {
      width: 40%;
      display: flex;
      justify-content: space-evenly;
      line-height: 0;
    }
  }

  .child {
    width: 20px;
    height: 20px;
    background: #f2f3f5;
  }

  // 发布评论的盒子 - 2
  .cmt-box {
    position: fixed;
    bottom: 0;
    left: 0;
    width: 100%;
    height: 80px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    font-size: 12px;
    padding-left: 10px;
    box-sizing: border-box;
    background-color: white;
    textarea {
      flex: 1;
      height: 66%;
      border: 1px solid #efefef;
      background-color: #f8f8f8;
      resize: none;
      border-radius: 6px;
      padding: 5px;
    }
    .van-button {
      height: 100%;
      border: none;
    }
  }
}
</style>
